Explanation #1: The Ri explains that this is due to filling in holes.

Refutation: This is not correct however, since it will then not tally with the other cases, which are forbidden because of Tikun K'li (repairing a vessel).

Explanation #2: Tosfos therefore establishes it by a new oven, which still contains stones and earth which have not yet been cleared out. Consequently, when one clears them out, it resembles 'G'mar Melachah', and one is Chayav because of Makeh ba'Patish ...

Explanation #2 (cont.): Since all G'mar Melachah is Chayav because of Makeh ba'Patish.

Question: The question remains however, that without Makeh ba'Patish, it is forbidden because of Muktzah, since the ashes and the stones are Muktzah?

Answer: From here the Ritzba extrapolates that the Chachamim waved Muktzah in face of Ochel Nefesh.

Conclusion: This is a further proof for what Tosfos wrote on Daf 8. DH 'Amar Rav Yehudah ... '.

Clarification: That one is permitted to move it to the side of the street, even though it is a Melachah.

Question: This implies that Ravina holds of Muktzah, since he compares it to 'a thorn in the street'; implying that otherwise it would be Muktzah.

Question (cont.): Whereas in Perek Mi she'Hichshich (Shabbos, Daf 157.) it implies that he holds like Rebbi Shimon, who doesn't hold of Muktzah ...

Question (concl.): Since Rav Acha and Ravina argue there - one is lenient and the other, strict; and wherever Rav Acha and Ravina argue, Rav Acha is stringent and Ravina, lenient.

Answer #1: Ravina here is going according to Rav Yehudah Amar Shmuel, who forbids moving a spit-rod, whilst he himself permits it.

Question: Still, there is a contradiction in Shmuel, since there in Perek Mi she'Hichshich, he holds like Rebbi Shimon, who does not hold of Muktzah, whereas here he holds of Muktzah.

Answer: A spit-rod is different, because after it has been used, it is no longer considered a K'li, and Shmuel therefore considers it Muktzah, even though, in principle, he holds like Rebbi Shimon.

Answer #2 (to previous question): [One can actually give the same answer to resolve the discrepancy in Ravina - Tosfos Yeshanim].

Clarification: This is mentioned in connection with a Mishnah, in Kesuvos (Daf 61.).

Question: Why does it not then mention 'Eifer Makleh', which is a Gemara in Makos (Daf 21:), which, according to Rav Papa, Rav Malkiyo said, whilst Rav Chin'na maintains that Rav Malkiyah said it.

Answer #1: What the Gemara means is 'Shefachos' and the opposite case, i.e. the middle one - 'Eifer Makleh'.

Answer #2: Alternatively, it means that the Mishnahs and the Beraisos were said specifically by Rav Malkiya and not Rav Malkiyo, whereas some of the Gemaras were by Rav Malkiyo ...

Conclusion: Even though Rav Malkiya said the Gemara of 'Eifer Makleh'. Hence it only gave a sign regarding the Beraisos.